-- Modified version of autodelimiter.lua
-- This version supports surround selection and autoremoving alone pairs
-- Please see pull request #33 (https://github.com/pkulchenko/ZeroBranePackage/pull/33) for more information
-- If you load this module and standard autodelimiter, the standard autodelimiter will be turned off to prevent collisions
local cpairs = {
  ['('] = ')', ['['] = ']', ['{'] = '}', ['"'] = '"', ["'"] = "'"}
local closing = [[)}]'"]]
local selection, spos, epos = ""
-- 自动插入（括号()、花括号{}、方括号[]、单引号''和双引号""）功能，扩展选择和移除独立的配对符号。
return {
  name = "Auto-insertion of delimiters",
  description = [[Extends auto-insertion of delimiters (), {}, [], '', and "" to add selection and removal of standalone pairs.]],
  author = "Paul Kulchenko (modified by Dominik Banaszak)",
  version = 0.42,
  dependencies = "1.30",

  onAppLoad = function(self)
    -- remove autodelimiter package to avoid conflicts
    if ide:GetPackage("autodelimiter") then
      ide:RemovePackage("autodelimiter")
      ide:Print("Disabled autodelimiter package to avoid conflict.")
    end
  end,
  onEditorKeyDown = function(self, editor, event)
    local currentpos = editor:GetCurrentPos()
    local keycode = event:GetKeyCode()
    if keycode == 8 then -- backslash
      if cpairs[string.char(editor:GetCharAt(currentpos - 1))] == string.char(editor:GetCharAt(currentpos)) then
        editor:DeleteRange(currentpos, 1)
      end
    end
    selection = editor:GetSelectedText()
		spos, epos = editor:GetAnchor(), editor:GetCurrentPos()
  end,
  onEditorCharAdded = function(self, editor, event)
    local keycode = event:GetKey()
    local hyphen = string.byte("-")
    local backslash = string.byte("\\")
    if keycode > 255 then return end -- special or unicode characters can be skipped here

    local char = string.char(keycode)
    local curpos = editor:GetCurrentPos()

    if closing:find(char, 1, true) and editor:GetCharAt(curpos) == keycode then
      -- if the entered text matches the closing one
      -- and the current symbol is the same, then "eat" the character
      if editor:GetCharAt(curpos - 2) ~= backslash then
        editor:DeleteRange(curpos, 1)
      end
    elseif cpairs[char] then
      if editor:GetCharAt(curpos - 2) ~= hyphen and editor:GetCharAt(curpos - 3) ~= hyphen then
      -- if the entered matches opening delimiter, then insert the pair
        editor:InsertText(-1, selection .. cpairs[char])
          if selection~='' then
          -- maintain selection.
            editor:SetAnchor(spos<epos and spos or spos+2)
            editor:SetCurrentPos(spos<epos and epos+2 or epos)
          end
      end
    end
  end,
}
